summaryrefslogtreecommitdiffstats
path: root/netwerk/test/unit/test_nsIBufferedOutputStream_writeFrom_block.js
blob: 577b2c6da8a98e082e4e6934f5b65078722ceb7c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
"use strict";

var CC = Components.Constructor;

var Pipe = CC("@mozilla.org/pipe;1", Ci.nsIPipe, "init");
var BufferedOutputStream = CC(
  "@mozilla.org/network/buffered-output-stream;1",
  Ci.nsIBufferedOutputStream,
  "init"
);
var ScriptableInputStream = CC(
  "@mozilla.org/scriptableinputstream;1",
  Ci.nsIScriptableInputStream,
  "init"
);

// Verify that pipes behave as we expect. Subsequent tests assume
// pipes behave as demonstrated here.
add_test(function checkWouldBlockPipe() {
  // Create a pipe with a one-byte buffer
  var pipe = new Pipe(true, true, 1, 1);

  // Writing two bytes should transfer only one byte, and
  // return a partial count, not would-block.
  Assert.equal(pipe.outputStream.write("xy", 2), 1);
  Assert.equal(pipe.inputStream.available(), 1);

  do_check_throws_nsIException(
    () => pipe.outputStream.write("y", 1),
    "NS_BASE_STREAM_WOULD_BLOCK"
  );

  // Check that nothing was written to the pipe.
  Assert.equal(pipe.inputStream.available(), 1);
  run_next_test();
});

// A writeFrom to a buffered stream should return
// NS_BASE_STREAM_WOULD_BLOCK if no data was written.
add_test(function writeFromBlocksImmediately() {
  // Create a full pipe for our output stream. This will 'would-block' when
  // written to.
  var outPipe = new Pipe(true, true, 1, 1);
  Assert.equal(outPipe.outputStream.write("x", 1), 1);

  // Create a buffered stream, and fill its buffer, so the next write will
  // try to flush.
  var buffered = new BufferedOutputStream(outPipe.outputStream, 10);
  Assert.equal(buffered.write("0123456789", 10), 10);

  // Create a pipe with some data to be our input stream for the writeFrom
  // call.
  var inPipe = new Pipe(true, true, 1, 1);
  Assert.equal(inPipe.outputStream.write("y", 1), 1);

  Assert.equal(inPipe.inputStream.available(), 1);
  do_check_throws_nsIException(
    () => buffered.writeFrom(inPipe.inputStream, 1),
    "NS_BASE_STREAM_WOULD_BLOCK"
  );

  // No data should have been consumed from the pipe.
  Assert.equal(inPipe.inputStream.available(), 1);

  run_next_test();
});

// A writeFrom to a buffered stream should return a partial count if any
// data is written, when the last Flush call can only flush a portion of
// the data.
add_test(function writeFromReturnsPartialCountOnPartialFlush() {
  // Create a pipe for our output stream. This will accept five bytes, and
  // then 'would-block'.
  var outPipe = new Pipe(true, true, 5, 1);

  // Create a reference to the pipe's readable end that can be used
  // from JavaScript.
  var outPipeReadable = new ScriptableInputStream(outPipe.inputStream);

  // Create a buffered stream whose buffer is too large to be flushed
  // entirely to the output pipe.
  var buffered = new BufferedOutputStream(outPipe.outputStream, 7);

  // Create a pipe to be our input stream for the writeFrom call.
  var inPipe = new Pipe(true, true, 15, 1);

  // Write some data to our input pipe, for the rest of the test to consume.
  Assert.equal(inPipe.outputStream.write("0123456789abcde", 15), 15);
  Assert.equal(inPipe.inputStream.available(), 15);

  // Write from the input pipe to the buffered stream. The buffered stream
  // will fill its seven-byte buffer; and then the flush will only succeed
  // in writing five bytes to the output pipe. The writeFrom call should
  // return the number of bytes it consumed from inputStream.
  Assert.equal(buffered.writeFrom(inPipe.inputStream, 11), 7);
  Assert.equal(outPipe.inputStream.available(), 5);
  Assert.equal(inPipe.inputStream.available(), 8);

  // The partially-successful Flush should have created five bytes of
  // available space in the buffered stream's buffer, so we should be able
  // to write five bytes to it without blocking.
  Assert.equal(buffered.writeFrom(inPipe.inputStream, 5), 5);
  Assert.equal(outPipe.inputStream.available(), 5);
  Assert.equal(inPipe.inputStream.available(), 3);

  // Attempting to write any more data should would-block.
  do_check_throws_nsIException(
    () => buffered.writeFrom(inPipe.inputStream, 1),
    "NS_BASE_STREAM_WOULD_BLOCK"
  );

  // No data should have been consumed from the pipe.
  Assert.equal(inPipe.inputStream.available(), 3);

  // Push the rest of the data through, checking that it all came through.
  Assert.equal(outPipeReadable.available(), 5);
  Assert.equal(outPipeReadable.read(5), "01234");
  // Flush returns NS_ERROR_FAILURE if it can't transfer the full amount.
  do_check_throws_nsIException(() => buffered.flush(), "NS_ERROR_FAILURE");
  Assert.equal(outPipeReadable.available(), 5);
  Assert.equal(outPipeReadable.read(5), "56789");
  buffered.flush();
  Assert.equal(outPipeReadable.available(), 2);
  Assert.equal(outPipeReadable.read(2), "ab");
  Assert.equal(buffered.writeFrom(inPipe.inputStream, 3), 3);
  buffered.flush();
  Assert.equal(outPipeReadable.available(), 3);
  Assert.equal(outPipeReadable.read(3), "cde");

  run_next_test();
});

// A writeFrom to a buffered stream should return a partial count if any
// data is written, when the last Flush call blocks.
add_test(function writeFromReturnsPartialCountOnBlock() {
  // Create a pipe for our output stream. This will accept five bytes, and
  // then 'would-block'.
  var outPipe = new Pipe(true, true, 5, 1);

  // Create a reference to the pipe's readable end that can be used
  // from JavaScript.
  var outPipeReadable = new ScriptableInputStream(outPipe.inputStream);

  // Create a buffered stream whose buffer is too large to be flushed
  // entirely to the output pipe.
  var buffered = new BufferedOutputStream(outPipe.outputStream, 7);

  // Create a pipe to be our input stream for the writeFrom call.
  var inPipe = new Pipe(true, true, 15, 1);

  // Write some data to our input pipe, for the rest of the test to consume.
  Assert.equal(inPipe.outputStream.write("0123456789abcde", 15), 15);
  Assert.equal(inPipe.inputStream.available(), 15);

  // Write enough from the input pipe to the buffered stream to fill the
  // output pipe's buffer, and then flush it. Nothing should block or fail,
  // but the output pipe should now be full.
  Assert.equal(buffered.writeFrom(inPipe.inputStream, 5), 5);
  buffered.flush();
  Assert.equal(outPipe.inputStream.available(), 5);
  Assert.equal(inPipe.inputStream.available(), 10);

  // Now try to write more from the input pipe than the buffered stream's
  // buffer can hold. It will attempt to flush, but the output pipe will
  // would-block without accepting any data. writeFrom should return the
  // correct partial count.
  Assert.equal(buffered.writeFrom(inPipe.inputStream, 10), 7);
  Assert.equal(outPipe.inputStream.available(), 5);
  Assert.equal(inPipe.inputStream.available(), 3);

  // Attempting to write any more data should would-block.
  do_check_throws_nsIException(
    () => buffered.writeFrom(inPipe.inputStream, 3),
    "NS_BASE_STREAM_WOULD_BLOCK"
  );

  // No data should have been consumed from the pipe.
  Assert.equal(inPipe.inputStream.available(), 3);

  // Push the rest of the data through, checking that it all came through.
  Assert.equal(outPipeReadable.available(), 5);
  Assert.equal(outPipeReadable.read(5), "01234");
  // Flush returns NS_ERROR_FAILURE if it can't transfer the full amount.
  do_check_throws_nsIException(() => buffered.flush(), "NS_ERROR_FAILURE");
  Assert.equal(outPipeReadable.available(), 5);
  Assert.equal(outPipeReadable.read(5), "56789");
  Assert.equal(buffered.writeFrom(inPipe.inputStream, 3), 3);
  buffered.flush();
  Assert.equal(outPipeReadable.available(), 5);
  Assert.equal(outPipeReadable.read(5), "abcde");

  run_next_test();
});